Hello! Saturday November 5^th was ‘Go Green’ day at the T? Gwyrdd.

The purpose of this event was to explore easy ways to save energy at home, and at the same time, to save money! Amongst these ideas were simple things, such as: walking to school, using a plug in the sink while washing up, turning off lights when leaving rooms, not leaving mobile phones to charge overnight and many more. For more ways of saving energy at home, follow this link: http://tiny.cc/w4iqr

Visitors to the ‘Go Green’ day were asked to choose one way of saving energy and pledge to introduce the change to their everyday lives.

To ensure everyone kept their pledges, we asked them to write their pledge on a leaf and attach it to the ‘Go Green’ tree. Before long the tree was full of pledges, ranging from walking to school to wearing a jumper around the house to keep warm.

By the end of the day, the little tree was full of green ideas! Fantastic!

It is worth noting that some visitors jumped at the chance to Go Green (literally!) by donning our green feather boa and glittery glasses! At times it looked more like a surreal episode of Strictly Come Dancing! I’m pretty sure it was the first time the dark slate floors of the T? Gwyrdd had seen such dance moves!

A big thank you to everyone who visited… the next event at the T? Gwyrdd is ‘Sustainable Christmas’ on December 3^rd, a chance to pick up tips for a green Christmas and a chance to try making your own Christmas decorations! If you have any suggestions on how to celebrate Christmas sustainably – let us know on Twitter: www.twitter.com/tygwyrdd

Thanks again, T? Gwyrdd

Over the last two weeks young scientists across the UK have planted seven thousand bulbs in order to help us understand climate change!

I've had many reports from teachers saying that their pupils are now really excited to start keeping weather records to help with this important investigation.  

I'd like to wish all the pupils well with their record keeping and can't wait to see the first weather records appear on our web pages this Friday! Please use the following links to help you record. Keeping weather records and What to record.

Don't forget to send me any pictures you have and I will add them to this blog page.

Question for the week: So far, this autumn has been a very warm one. Infact, October was the eighth warmest in the last 100 years!  Do you think November will stay warm or turn cold? Do you think it could snow? What weather would you like to have? Leave your comments below.

Many Thanks

Professor Plant

As mentioned in the previous post, the only way to advance the study of this large blocklift was to take x-rays of the excavated ‘features’, in order to get a better idea of the condition of the archaeological metals, and to see if there were objects beneath the ones excavated. For this to happen, the five features had to be separated and lifted in miniature blocklifts.

As readers can see by the first photograph which shows the whole soil block after the completion of micro-excavation, separating features was a difficult task: whilst feature 1 was a discrete item, easily removed from the rest of the block, I had to make certain executive decisions about breaking up the rest of the block. Where possible, I tried to divide the features from each other using the cracks that were already present in the block, or by cutting over and under overlapping features. Inevitably, some damage did occur to the peripheries of features during the lifting process.

The process of blocklifting was remarkably easy: effectively, I blocklifted these features in the same way that they were lifted on site, except that as I was working in a laboratory, I had the opportunity to use conservation-grade materials in a much more controlled environment.

To begin with, I had to stabilise the artefacts in preparation for a process which would jar them quite a lot. I first consolidated the exposed artefacts using a removable adhesive called Paraloid B72, and then added a layer of melted wax, called Cyclododecane, to provide a more intimate support. Handily, this layer will eventually sublime by itself.

I then wrapped features in Clingfilm, to act as a barrier layer between the archaeology and the rigid material I would use hold the block together. For this, I selected polyurethane foam (readers may have come across this whilst completing DIY projects; it is often used as an insulating filler), as it has a very low density, and will not interfere with the attainment of an image of the mineralized iron plate. Polyurethane is prepared by mixing two liquid components together, and could be poured around the covered feature, reaching all nooks and crannies. Walls of plastic card and clay had been built around the feature to enclose the polyurethane.

Once the polyurethane had hardened, I began to pedestal the feature being lifted, before undercutting it. The separated feature could be turned over, and large amounts of extraneous burial deposit removed, which would have otherwise interfered with x-raying the metal artefacts.

I repeated this process until all the features were lifted, and prepared for X-radiography.

After having managed to break the large soil block up into small enough blocks to get into the x-ray machine, I finally began the task of x-raying the archaeological artefacts.

For this, I had the chance to use the Museum’s newly acquired computerised radiography system. Here, instead of using the traditional wet-plate method requiring film and much time spent in a dark room, we use a phosphor plate which can be used around 1000 times. This plate is read by a scanner, and an image produced within about 45 seconds.

This new system has allowed us to capture so much more detail about the inside of the blocks and the condition of the armour than would ever have been possible using the traditional method. The x-ray records the density of materials at every point, and the software used to view the image allows for manipulation in much the same way as programs like Photoshop: we can zoom into areas of the image, adjust brightness and contrast, apply filters, invert the negative, etc. Thus far all of the features have been x-rayed, and the results have been astounding: I have included copies of the images, complete with annotations. It would appear that a lot more existed beneath the surface excavated than previously supposed.

I had hoped that the x-rays could be used as a guide for further excavation of the features and eventual extraction of the artefacts: however, the condition of the metal inside suggests almost complete mineralization of the iron, and cautions against this course of action. The most that can really happen with these soil blocks now is that they are extensively x-rayed, and stored safely in case of future research.

Aside from highlighting areas of interest on the x-rays, and explaining certain phenomenon, my role as conservator for this project has come to an end. Now, curators, archaeologists and specialists will have to identify objects in the x-rays, marry up these images with the photographic record of my excavation, and begin to tie this information into the narrative of the site overall.